Historian John Turner recently upped the ante with his acclaimed biography, Brigham Young: Pioneer Prophet. They book shows a deeply flawed Brigham whose words and deeds sometimes run strongly counter to Mormon expectations of a prophet. Taking this warts-and-all treatment into account, a common criticism of the biography was that Turner didn’t convincingly answer the question, “With all his flaws, why was this Brigham Young revered and/or looked up to as a prophet?”

I honestly thought that in the book I explained pretty clearly why 19th-century Latter-day Saints followed Brigham Young. Not everybody did, but of those that followed him, I think the two things that most cemented and affirmed his leadership were the completion of the Nauvoo Temple and the successful pioneer trek and early settlement of the Salt Lake Valley. Those were incredibly significant accomplishments in very different ways that [affirmed both] his priestly and his practical leadership.

And I think those sorts of accomplishments built a very deep reservoir of support. So when the Latter-day Saints faced major setbacks, such as during the Utah War, it was possible for people to move forward, perhaps along the lines that Brigham Young could move forward after setbacks in Ohio or Missouri.
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Also, it was very significant that he had led the mission to England in the 1840s. A lot of the early emigrants to Nauvoo, and then to Utah, were people who’d known Brigham Young for many years. He’d maybe help lead them into the church.

Turner goes on:

I think some of those issues that you raise didn’t trouble 19th-century Mormons the way they would trouble 21st-century Mormons. Latter-day Saints today would never expect President Thomas Monson to talk or act the way that Brigham Young did. But that’s part of the foreignness of the past. And I actually think it’s a very healthy thing for, not just Latter-day Saints, but for human beings to get a sense of just how incredibly foreign the past is. People are strange. They seem strange, they seem different. They don’t necessarily have the same values and sensibilities that we do. And that’s one of the foremost lessons of studying history. And I think it’s very beneficial in many ways to always be reminded of that and not expect people in the past to act the way that we do.

Now, even putting those sensibilities aside, I think there are aspects of Brigham Young’s leadership that are deeply troubling, but I don’t think it should be difficult to understand why 19th-century Latter-day Saints followed him.